The Mouth-parts of the Ncmocera. By W. Wesclie. 13 



bear more or less developed sense-organs. In Trineura aterrima V. 

 this sense-organ is similar to that on the four-join ted palpus in 

 some of the Bibionidse (plate III. figs. 42, 4G, 51). 



The relationship to the Dolichopodidae is shown not only by 

 the' toothed labrum and its greater development, but also by a 

 pubescence on this part, that being a character mostly confined t<> 

 the Dolichopoclida? ; the deep channelled hypophaiynx especially 

 when viewed from the side is also similar to that found in some 

 genera of 'the larger family. The hairs laterally placed on each 

 side of the median suture of the mentum in some Dolichopodida\ 

 Lonchopteridas, and Phoridge also point to a relationship. The 

 deeply cleft labium, the plates, the arrangement of the tracheae 

 and taste-hairs on the paraglossa? also indicate an affinity to 

 Leptis. 



The predaceous habits of the Phorida? have been alluded to as 

 probable, and I have now some evidence in support of that view. 

 I have a small Acalyptrate Muscid which I took out of the 

 grasp of P. concinna ; both are mounted on the same card. I 

 have made inquiries and it seems that the observation is rare, 

 as those who have studied this family, like Dr. J. H. Wood, who 

 has paid great attention to it, have not had a similar experience. 

 But the contents of the abdomen in many preparations strengthens 

 me in my opinion, as they present the appearance found in blood- 

 sucking and predatory insects, a subject to which I have of late 

 paid some attention. Add to this the markedly predaceous 

 character of the mouth-armature, and it can be seen that these 

 minute insects can find weaker organisms to prey on. Packard says, 

 probably deriving his information from "Williston, that different 

 species feed on both living and dead insects and sometimes decay- 

 ing vegetable matter* — and this is possibly an observation of the 

 North American species. 



Group -5. — The list of species in which the remains of palpi 

 have been found contains two wrong determinations : Myiocera 

 carinifrons Fin. is Phorocera serriventrisllnd., and Anthomyia sulci- 

 ventris Ztt. is Phorlia ignota End. These remnants of palpi 

 occur so often that it is not necessary to add to the list already 

 published ; it may, however, be pointed out (1) that they are most 

 strongly marked in the Cyrtoneurinse section of the Muscidse 

 and the Myckeinre section of the Anthomyida: ; (2) and fail in 

 specialised forms such as Stomoxys, Glossina, Siphona, Prosena, or 

 Drymk > ; (3) and in those genera where the fourth longitudinal 

 vein completely closes the cell and has left the margin; (4) or the 

 teeth on the paraglossce are much developed and the eyes air 

 separated in the males (the Camosina3 section of the Anthomyi 

 and the Cordyluridse). 



* Entomology for Beginners New York : Holt and Co., 3rd ed., 1899, p. 126. 



